(530h) Catalytic Conversion of Biomass Derived Ethanol to Advanced Hydrocarbon Fuels and Valuable Chemicals

Li, Z., Oak Ridge National Laboratory
Lepore, A. W., Oak Ridge National Laboratory
Salazar, M., Oak Ridge National Laboratory
Davison, B. H., BioEnergy Science Center and Oak Ridge National Laboratory
Narula, C., Oak Ridge National Laboratory
Global ethanol production is increasing rapidly and anticipated to reach more than 33 billion gallons by 2017. The ethanol market is at a saturation point in transportation sector since its use is limited by the 10-15% blend-wall due to technological and infrastructure constraints. Therefore, it is expected that excess ethanol will be available as a platform molecule for the production of advanced hydrocarbon fuels and value-added chemicals. We will present our findings in exploring conversion of ethanol into hydrocarbon fuels and valuable co-products (e.g., benzene, toluene and xylenes (BTX)). Selective conversion of ethanol over Ga-ZSM-5 will be presented. At 450 ºC and 0.4 h-1, Ga-ZSM-5 produces 55% BTX which is two-fold increase over H-ZSM-5 (26% BTX). The BTX yield increases with increase in temperature (300-500 ºC) and Ga loading (0.5% to 6.2%). Enhanced hydrogen production and reduced light paraffins (propane and butane) formation are also observed with the increase of Ga loading. The role of Ga in promoting BTX formation and molecular hydrogen production will be discussed. The active gallium species will be further presented from the studies of physical mixture experiments and extensive catalyst characterizations. We will also discuss our findings in alternative zeolite structures for ethanol conversion, and the effect on product selectivity and catalyst stability.